the single most important thing about learning biochem is to not get fixated on the details... always learn the general overview before you start applying the details. the reason is that you can get totally lost trying to memorize the steps/enzymes of TCA, glycogen degrade/synthesis, pentose pathway, glycolysis, amino acid metabolism, fatty acids, etc. generally, they're not going to ask you minute specifics like "in the conversion of malate to oxaloacetate in the TCA cycle, what is the product and enzyme required?"... it's much more likely that you'll see stuff like "what's the effect of glucagon on glycogen synthesis, degradation, glycolysis, and fatty acid synthesis/B-oxidation?" so you'll be better off if you can actually see the anapleurotic reactions, the general regulation, and the overlap between these processes.
i don't know if i would suggest Lippincott. it's a good book, and a lot of med students use it for Step1. but if you're taking it as an undergrad (for the first time), review books generally will gloss over too much detail and not enough explanation, plus they're dense reading. i would go with Lehninger; it's well written, has a wide scope, lots of pictures (plus a CD), and easily understandable. as with any text, i don't recommend reading it word for word... instead, use it as a source and refer to it as needed.
